Oil will be slippery and smell like oil. Coolant will be more water-y and also slippery but not as slippery as the oil. Washer fluid is closest to water out of the 3. Kinda hard to explain over the internet.

These are the best methods to tell which type of leak you have. Grab a bucket and let it drip. Once you have that figured out, you will have to find where it is coming from.